Manufacture of Carbon Materials with High Nitrogen Content.

Nowadays one of the biggest challenges for carbon materials is their use in CO2 capture and their use as electrocatalysts in the oxygen reduction reaction (ORR). In both cases, it is necessary to dope the carbon with nitrogen species. Conventional methods to prepare nitrogen doped carbons such as melamine carbonization or NH3 treatment generate nitrogen doped carbons with insufficient nitrogen content. In the present research, a series of activated carbons derived from MOFs (ZIF-8, ZIF-67) are presented. Activated carbons have been prepared in a single step, by pyrolysis of the MOF in an inert atmosphere, between 600 and 1000 °C. The carbons have a nitrogen content up to 20 at.% and a surface area up to 1000 m2/g. The presence of this nitrogen as pyridine or pyrrolic groups, and as quaternary nitrogen are responsible for the great adsorption capacity of CO2, especially the first two. The presence of Zn and Co generates very different carbonaceous structures. Zn generates a greater porosity development, which makes the doped carbons ideal for CO2 capture. Co generates more graphitized doped carbons, which make them suitable for their use in electrochemistry.

Nanoscopic Structural Fluctuations of Disassembling Microtubules Revealed by Label-Free Super-Resolution Microscopy.

Microtubules are cytoskeletal polymers of tubulin dimers assembled into protofilaments that constitute nanotubes undergoing periods of assembly and disassembly. Static electron micrographs suggest a structural transition of straight protofilaments into curved ones occurring at the tips of disassembling microtubules. However, these structural transitions have never been observed and the process of microtubule disassembly thus remains unclear. Here, label-free optical microscopy capable of selective imaging of the transient structural changes of protofilaments at the tip of a disassembling microtubule is introduced. Upon induced disassembly, the transition of ordered protofilaments into a disordered conformation is resolved at the tip of the microtubule. Imaging the unbinding of individual tubulin oligomers from the microtubule tip reveals transient pauses and relapses in the disassembly, concurrent with increased organization of protofilament segments at the microtubule tip. These findings show that microtubule disassembly is a discrete process and suggest a stochastic mechanism of switching from the disassembly to the assembly phase.

Fast Leaps between Millisecond Confinements Govern Ase1 Diffusion along Microtubules.

Diffusion is the most fundamental mode of protein translocation within cells. Confined diffusion of proteins along the electrostatic potential constituted by the surface of microtubules, although modeled meticulously in molecular dynamics simulations, has not been experimentally observed in real-time. Here, interferometric scattering microscopy is used to directly visualize the movement of the microtubule-associated protein Ase1 along the microtubule surface at nanometer and microsecond resolution. Millisecond confinements of Ase1 and fast leaps between these positions of dwelling preferentially occurring along the microtubule protofilaments are resolved, revealing Ase1's mode of diffusive translocation along the microtubule's periodic surface. The derived interaction potential closely matches the tubulin-dimer periodicity and the distribution of the electrostatic potential on the microtubule lattice. It is anticipated that mapping the interaction landscapes for different proteins on microtubules, finding plausible energetic barriers of different positioning and heights, can provide valuable insights into regulating the dynamics of essential cytoskeletal processes, such as intracellular cargo trafficking, cell division, and morphogenesis, all of which rely on diffusive translocation of proteins along microtubules.

Quejas de memoria: salud mental, enfermedades, dolor y soledad. Estudio poblacional en la ciudad de Madrid / Memory complaints: mental health, diseases, pain and loneliness. A population study in the city of Madrid

Introducción: Las quejas subjetivas de memoria (QSM) se consideran predictoras del deterioro cognitivo, pero se asocian también a otros factores; los sociales y los hábitos de vida han sido los menos estudiados. Objetivo: Valorar las QSM y su asociación con variables epidemiológicas, de salud, sociales y hábitos de vida. Sujetos y métodos: Estudio epidemiológico trasversal de la población de Madrid elegida aleatoriamente según censo. Entrevista telefónica. Población diana: 1.775 mayores de 55 años. Se preguntó sobre QSM, aspectos sociales, económicos, de salud y hábitos de vida. Se administraron el cuestionario de salud general de Goldberg (GHQ) y el cuestionario de calidad de vida COOP-Wonca. Resultados: Encontramos asociación estadísticamente significativa de las QSM con la edad, la orientación temporal, todas las variables relacionadas con la salud mental (depresión), la ansiedad, el sueño, la salud mental/GHQ y la calidad de vida. Se halló asociación con todas las variables que miden el dolor y con sentir soledad. No hubo asociación con enfermedades específicas, excepto con la alergia crónica y las ligadas al dolor. Los predictores de las QSM fueron la orientación temporal, la multimorbilidad, la salud mental/GHQ, la ansiedad, el dolor y el sentir soledad. Conclusiones: Las QSM son un síntoma con múltiples causas. Se asocian a menor rendimiento de la memoria, pero también a variables relacionadas con la salud, los aspectos sociales y el tipo de vida. Ante un paciente con QSM, que pueden deberse al deterioro cognitivo por enfermedad de Alzheimer, deben considerarse estas asociaciones para valorar dicho riesgo y saber cuándo es más necesario un seguimiento

Introduction: Subjective memory complaints (SMC) are considered predictor of cognitive impairment, but are also associated with other factors; social and lifestyle have been the least studied. Aim: To evaluate SMC and their association with epidemiological, health, social and lifestyle variables. Subjects and methods: Cross-sectional epidemiological study of the randomly selected population of Madrid. Telephone interview. Target population: 1,775 over 55 years of age. We asked about QSM, social, economic, health and lifestyle aspects. The Goldberg General Health Questionnaire (GHQ) and the COOP-Wonca Quality of Life Questionnaire were administered. Results: We found statistically significant association of SMC with age, temporal orientation, all variables related to mental health (depression), anxiety, sleep, mental health/GHQ, and quality of life. Association was found with all pain variables and with loneliness. There was no association with specific diseases, except chronic allergy and those linked to pain. The predictors of the SMC were temporal orientation, multimorbidity, mental health/GHQ, anxiety, pain and feeling lonely. Conclusions: SMC is a multi-caused symptom. They are associated with lower memory performance, but also with variables related to health, social aspects and lifestyle. When faced with a patient with SMC, which may be due to cognitive impairment because of Alzheimer’s disease, these associations should be taken into account to assess this risk and know when follow-up is most needed

Immunosensing platform based on gallium nanoparticle arrays on silicon substrates.

Gallium nanoparticles (GaNPs) of different sizes are deposited on Si(100) substrates by thermal evaporation. Through ellipsometric analysis, it is possible to investigate the plasmonic effects in the GaNPs and exploit them to develop biosensors. The excitation of the resonant modes for certain incidence angles leads to negative values of the imaginary part of the pseudodielectric function (<εi>) obtained in ellipsometry. Furthermore, there is an abrupt sign change when the difference between the phase shifts of p- and s-polarization components reaches 180° at an energy of around 3.15 eV. At that energy, reversal of the polarization handedness (RPH) occurs for an elliptically-polarized input beam. The energy of the RPH condition reduces as the evaporation time increases. The slope of <εi> at the RPH condition is extremely sensitive to changes in the surrounding medium of the NP surface and prompts the use of the GaNP/Si system as sensor platform. Fourier transformed infrared spectroscopy (FTIR) is used before and after functionalization with 3,3'-dithiodipropionic acid di(N-succinimidyl ester) and a glutathione-specific antibody to confirm the chemical modification of the sample surface. The developed immunosensor is exposed to different concentrations of glutathione (GSH) showing a linear relationship between the slope of the pseudodielectric function at the RPH condition and the GSH concentration. The immunosensor shows a limit of detection of 10nM enabling its use for the detection of low GSH levels in different medical conditions.

Glutathione immunosensing platform based on total internal reflection ellipsometry enhanced by functionalized gold nanoparticles.

An immunosensor to detect small molecules, such as glutathione (GSH), has been developed by combination of ellipsometry and Kretschmann surface plasmon resonance (SPR). The Au thin film used for surface plasmon polariton (SPP) excitation is functionalized with anti-GSH to specifically bind GSH. At low concentrations, the small refractive index changes caused by the low molecular weight of GSH induced only negligible shifts in the plasmon resonant energy during GSH binding. To improve sensitivity, gold nanoparticles (AuNPs) are functionalized with glutathione acting as amplifiers of the antigen-antibody interaction. Changes induced by the AuNP adsorption are monitored using Ψ and Δ ellipsometric functions. After performing competitive assays using solutions containing different concentrations of free GSH and a constant amount of functionalized AuNPs, it was concluded that the resonant energy linearly shifts as the relative concentration of free GSH increases. A detection limit for free GSH in the nanomolar range is found, demonstrating the effectiveness of AuNPs to enhance the sensitivity to immunoreactions in total internal reflection ellipsometry.

[Relationship between memory complaints and memory performance, mood and sociodemographic variables in young adults]. / Relacion de las quejas de memoria con el rendimiento de memoria, el estado de animo y variables sociodemograficas en adultos jovenes.

INTRODUCTION: Neurological consultations due to memory complaints have increased in recent years in both older and younger people. Few investigations have studied the variables related to memory complaints in young adults. AIM: To analyze, in a sample of young adults, the relationship between memory complaints and objective memory performance, depressive and anxiety symptoms, age, sex and level of studies. SUBJECTS AND METHODS: The study included 582 healthy workers, without cognitive impairment, aged 22-64 years. ASSESSMENT: Word List and Family Scenes of Wechsler Memory Scale-III, Memory Failures of Everyday Questionnaire (MFE) and Goldberg Anxiety and Depression Scale. RESULTS: We did not find any significant association between subjective assessment of memory and objective performance, both immediate and delayed in verbal and visual memory. Depression and anxiety had the highest correlation with MFE. The significant variables in the multiple regression analysis were: depression, with the largest effect size, age, college studies and sex. CONCLUSION: In young adults, those which had a greater perception of daily forgetfulness were not those with lesser memory performance. The most important variables involved in memory complaints were depression and anxiety. Younger people, people with college education and men reported less memory complaints.

TITLE: Relacion de las quejas de memoria con el rendimiento de memoria, el estado de animo y variables sociodemograficas en adultos jovenes.Introduccion. Las consultas en neurologia por quejas de memoria se han incrementado en los ultimos años, tanto en mayores como en jovenes. Se han realizado pocos estudios sobre las variables que influyen en las quejas en adultos jovenes. Objetivo. Analizar en esta poblacion la relacion de las quejas con el rendimiento objetivo de memoria, con la depresion y la ansiedad, con la edad, el sexo y el nivel de estudios. Sujetos y metodos. Muestra de 582 individuos trabajadores sin deterioro cognitivo y edad de 22-64 años. Los materiales utilizados fueron listas de palabras y escenas de familia de la escala de memoria de Wechsler, tercera edicion, cuestionario de fallos de memoria de la vida diaria (MFE), y escala de depresion y ansiedad de Goldberg. Resultados. No se encontro asociacion estadisticamente significativa entre la valoracion subjetiva de la memoria y el rendimiento objetivo inmediato o demorado, ni en la memoria visual ni en la verbal. La depresion y la ansiedad fueron las variables con mayor correlacion con la puntuacion global del MFE. En el analisis de regresion, las variables significativas fueron: la depresion, con el mayor tamaño de efecto, la edad, los estudios universitarios y el sexo. Conclusion. Las personas jovenes que manifestaron mas olvidos cotidianos no presentaron un rendimiento menor en las pruebas objetivas de memoria. Las variables mas importantes que intervinieron en las quejas fueron la depresion y la ansiedad. Las personas mas jovenes, las que tenian estudios universitarios y los varones manifestaron menos quejas de memoria.

Quejas subjetivas de memoria en adultos jóvenes y su relación con rendimiento de memoria, depresión, calidad de vida y rasgos de personalidad / Subjective memory complaints in young adults and their relationship to memory performance, depression, quality of life and personality traits

Introducción y objetivos: Hay enfermedades degenerativas que pueden presentarse en adultos jóvenes y que afectan a la memoria; para ellas es importante un diagnóstico precoz. Las quejas subjetivas de memoria (QSM) son cada vez más frecuentes en adultos jóvenes, pero han sido o bjeto de pocos estudios. Nuestro objetivo es analizar la relación entre las QSM y el rendimiento objetivo de memoria, y determinar la asociación de las QSM con variables relacionadas con el estado de ánimo, los rasgos de personalidad y la percepción de la calidad de vida relacionada con la salud. Material y métodos: Estudiamos a 102 sujetos, de entre 23-64 años y sin deterioro cognitivo. Evaluación: Cuestionario de Fallos de Memoria, Escala de Memoria de Wechsler, Escala de Depresión-Ansiedad de Goldberg, Escala de Resiliencia y Cuestionario de Salud SF-12. Se realizaron correlaciones y regresión lineal jerárquica en tres bloques: variables sociodemográficas, de salud y de rendimiento de memoria. El tamaño del efecto se estudió con R2. Resultados: No hay correlación significativa entre QSM y edad, estudios, memoria auditiva y visual, ansiedad y resiliencia. Existe una correlación estadísticamente significativa con sintomatología depresiva (r=0,35; p<0,01) y percepción de salud (r=0,37; p<0,01). Varios factores del SF-12 y de personalidad se asociaron a las QSM. Entre todas las variables, la única con valor predictivo en la regresión fue Salud mental (F=3,561; p=0,004; R2=0,23). Conclusión: Nuestro estudio destaca el aspecto subjetivo de las QSM frente al objetivo. En adultos jóvenes que acuden a la consulta con QSM hay que valorar factores como la ansiedad la depresión, la falta de confianza en uno mismo y la calidad de vida, y no sólo el rendimiento de memoria(AU)

Introduction and aims: There are degenerative diseases in young adults that can affect memory; for these diseases an early diagnosis is important. Subjective memory complaints (SMC) are becoming more common in young adults but there are few studies on this topic. Our aim is to analyze the relationship between SMC and objective memory performance and to establish the association between SMC and mood, personality traits or perception of quality of life related to health. Methods: We studied 102 subjects, between 23-64 years without cognitive impairment. Assessment: Questionnaire of Memory Failures of Everyday, Wechsler Memory Scale, Goldberg Anxiety and Depression Scale, Resilience Scale and Health Survey (SF-12). Statistical analysis: Correlations and hierarchical linear regression in three blocks: sociodemographic factors, health factors and memory performance. The effect size was studied using R2. Results: No significant correlation between SMC and age, education, auditory and visual memory, anxiety and resilience, was found. There is a statistically significant correlation with depressive symptoms ('r' = 0.35, p<0.01) and health perception ('r' = 0.37, p<0.01). Several SF-12 and personality factors were associated with SMC. Among all variables, the only one with predictive value in the regression was 'Mental Health' (F=3.561, P=0.004, R2=0.23). Conclusion: Our study highlights the subjective aspect of the SMC against the objective one. Attending young adults with SMC we must evaluate factors such as anxiety, depression, lack of self-confidence and quality of life and not only memory performance(AU)

Coupling characterization and noise studies of the optical metrology system onboard the LISA Pathfinder mission.

We describe the first investigations of the complete engineering model of the optical metrology system (OMS), a key subsystem of the LISA Pathfinder science mission to space. The latter itself is a technological precursor mission to LISA, a spaceborne gravitational wave detector. At its core, the OMS consists of four heterodyne Mach-Zehnder interferometers, a highly stable laser with an external modulator, and a phase meter. It is designed to monitor and track the longitudinal motion and attitude of two floating test masses in the optical reference frame with (relative) precision in the picometer and nanorad range, respectively. We analyze sensor signal correlations and determine a physical sensor noise limit. The coupling parameters between motional degrees of freedom and interferometer signals are analytically derived and compared to measurements. We also measure adverse cross-coupling effects originating from system imperfections and limitations and describe algorithmic mitigation techniques to overcome some of them. Their impact on system performance is analyzed within the context of the Pathfinder mission.

Deep phase modulation interferometry.

We have developed a method to equip homodyne interferometers with the capability to operate with constant high sensitivity over many fringes for continuous real-time tracking. The method can be considered as an extension of the "J1 . . .J4" methods, and its enhancement to deliver very sensitive angular measurements through Differential Wavefront Sensing is straightforward. Beam generation requires a sinusoidal phase modulation of several radians in one interferometer arm. On a stable optical bench, we have demonstrated a long-term sensitivity over thousands of seconds of 0.1 mrad/√Hz that correspond to 20 pm/ √Hz in length, and 10 nrad/ √Hz in angle at millihertz frequencies.